Vehicle vacuum chamber leak testing device

ABSTRACT

A mannually operated vacuum device, particularly adapted to use the engine running vacuum to detect the leaks in a vacuum chamber of ignition distributors, automatic transmission, heater controls antipolution devices, etc.; without removal thereof from the vehicle. The device includes an operation mechanism and a leak indication mechanism connected by a main passage arranged to connect the engine intake manifold to the vacuum chamber to be checked. The operating mechanism includes a valve along said main passage and a button to selectively open and close the valve. The leak indication mechanism includes diaphragm, and indicator fixed to the latter, and a return spring whereby a leak will be indicated by the displacement of the indicator.

United States Patent Caron VEHICLE VACUUM CHAMBER LEAK TESTING DEVICEPrimary Examiner-Richard C. Queisser Assistant Examiner-Joseph W. Roskos5 7] ABSTRACT A mannually operated vacuum device, particularly adaptedto use the engine running vacuum to detect the leaks in a vacuum chamberof ignition distributors, automatic transmission, heater controlsantipolution devices, etc.; without removal thereof from the vehicle.The device includes an operation mechanism and a leak indicationmechanism connected by a main passage arranged to connect the engineintake manifold to the vacuum chamber to be checked. The operatingmechanism includes a valve along said main passage and a button toselectively open and close the valve. The leak indication mechanismincludes diaphragm, and indicator fixed to the latter, and a returnspring whereby a leak will be indicated by the displacement of theindicator.

4 Claims, 3 Drawing Figures PATENTEI] JAN 2 2 I974 VEHICLE VACUUMCHAMBER LEAK TESTING DEVICE The present invention refers to a new devicepermitting the testing of the tightness of vacuum chambers on vehicleswith engine vacuum; these vacuum chambers are used on ignitiondistributors, automatic transmissions, heater controls, also on mostantipollution devices on automobiles.

It is current practice for mechanics to proceed by substitution or tocreate vacuum with their mouth to detect a leak in the vacuum chamber ofthese various mechanisms. Also, test-benches for ignition distributorsare equipped with a vacuum pump pennitting the checking for tightness,when the distributor is installed on tester. However, most garagistshave no distributor test-bench, due to the high cost. The vacuum chamberis more and more frequently used in operation of various mechanisms onlate vehicle models such asantipolution systems. The abovementionedactual checking methods are not in accordance with the effectivestandards required, and have many inconveniences. It is obvious that thefirst method constitutes a notable loss of time in trial and errorby-substitution, and that with the second method it is not possible todetermine with certainty the real condition of the vacuum chamber. Thethird method, when it is possible to use it, necessitates the unitremoval from the vehicle, what unnecessarily'extends the duration of thetest. Also, proper operation of vacuum pumps used on distributortest-benches is highly affected by this kind of test; dueto harmfullparticles which penetrate into the pump and contribute to a prematurepump failure.

I have discovered that these inconveniences would be eliminated by aneasy method, which permits rapid checking for tightness of all vacuumchambers used on vehicles, using a new device specially made for thispurpose. It is now possible at low cost for all garagists, to use theengine vacuum to detect a leak in a vacuum chamber or connecting hosesthereof with certainty and in short order. The device includes a housingwhich there are two connecting sleeves or nipples equipped with hoses;at one end of the housing a hose permits the connection to the vacuumintake manifold, and at the other end of the housing the other hoseallows connection to the main tube of the vacuum chamber of a unit to bechecked. An operating valve located in the housing permits a simplethumb action to open and hermetically close a main passage joining thetwo connecting sleeves. A leak indicator fixed to a diaphragm is locatedin the housing and plunges into it on vacuum effect. A spring engagingthe diaphragm, pushes out the indicator, when the vacuum is replaced byair coming in through a leak, thereby revealing the leak.

When the device is installed and the engine is running, it suffices topress down the operating button, with a light pressure, for a fewseconds, to obtain a vacuum inside the vacuum chamber. The release ofthe operating button permits the automatic sealed closing of the mainpassage, and thus shorts off both connecting sleeves. The lower orinward position of the indicator is a no leak indication and vacuum willsubsist. In the opposite case, the outward position of the indicator,

is. In such a way the test can be made in only a few minutes.

In referring to the illustrating drawings representing a preferredembodiment of the testing device:

FIG. 1 is a cross-sectional view of a testing device according to theinvention as seen along the line l-] in FIG. 2;

FIG. 2 is a top view of a testing device according to the invention;

FIG. 3 is a right end view of the testing device shown in FIGS. 1 and 2.

The references are numbered from I to 21, in the assembling order.

The illustrated testing device is made of nylon, and most componentparts are fashioned with precision on a lathe and fixed under pressurewith some thousandths of an inch of tension. Housing 1 is a rectangularnylon block with square ends, and with slightly rounded off exteriorangles. A one-eighth of an inch diameter hole is drilled throughlengthwise in housing 1, to constitute the main passage. Other holes ofdifferent dimensions are so drilled in housing 1, to receive thecomponent parts. Also, it may be made from a moulded part, or in twoparts by the injection process to eliminate some extemalparts and time,andto obtain the same results with the least cost in production.

The return spring 2, is located in a hole under diaphragm 4 and the leakindicator 3 and keeps them in upper return position against retainer 7,with appropriate force when the vacuum is replaced by air. The leakindicator 3 is mounted on diaphragm 4, by washer 5 and nut 6. Thediaphragm 4 is held hermetically sealed in place by retainer 7, which isfixed under pressure.

' tive clearance of 0.001 inch. Thus in this manner spring each vacuumchamber should be checked separately, 1

so as to determine the faulty chamber where the leak 2, leak indicator3, diaphragm 4, washer 5, nut 6 and retainer 7, constitute the wholemechanism for the lea indication in the housing. a

Diaphragm 4 is made from a very flexible thin material disc in such away to permit its movement in the oval space, as indicated.

The operating rod 8 islocated in a hole of housing I in which it canmove freely with an approximative clearance of 0.002 of an inch. Itsupper stroke is determined by a lower part enlargement of operating rod8, in housing 1 support well. It permits the opening of operating valve12, when the operator presses down on operating button 9, which is fixedunder pressure on the operating rod 8, so that the operation will beeasier. The flexible seal disc 10, assures the tightness of the upperpart of the valve seat 11 and operating valve 12. It constitutes thecontact point for the rod 8 with valve 12. I

The valve seat 11, is a round part fixed under pressure in housing 1; totightly fix the flexible seal disc 10. Its upper surface is slightlyconcave; permitting the free movement of the operating rod 8 and theflexible seal disc 10.

In its center a taper hole is precisely fashioned upright, with thesmall diameter at the upper end. It constitutes the so called seat ofthe operating valve 12. A A; inch diameter hole is drilled across and inthe middle of valve seat 11, as indicated to complete the main passage.The valve seat 11, may be made from resilient material with the use of ahard material operating valve 12, or vice versa, but the first processis better.

The operating valve 12 is precisely fashioned taper so that its contourfits hermetically to seat 11. It permits the closing and opening of themain passage, as required by the operator. Valve 12 is of the floatingtype, so as to obtain an effective adjustment on seat 11, withoutconstraint on the other parts of the mechanism; to assure the hermeticclosing of the main passage; essential condition for the properoperation of the device.

The flexible seal disc 13, assures the tightness of the lower end of thevalve seat 11 and operating valve 12. It constitutes the contact-pointof valve 12 with the spring seat 14 and spring 15. So that they canaccomplish an effective action; the flexible seal discs and 13 are madeof very flexible and resistant thin material discs, which cover theentire surface. The spring seat 14 mounted on spring 15, assures theprotection of seal disc 13, against the rough angles of spring 15.Spring 15 is of appropriate pressure and assures the complete closing ofvalve 12, when the operating button 9 is released by the operator.

Retainer 16 is a cylindrical part fixed under pressure in housing 1, soas to fix tightly the flexible seal disc 13. Its upper surface isslightly concave, permitting the free movement of operating valve 12 andof flexible seal disc 13. In its center, a 5/16 inch diameter hole isdrilled upright from the upper surface to within ytinch of the lowersurface, to receive the return spring 15. From this point, a inchdiameter hole is drilled through to the lower surface, as indicated.This hole constitutes an opening to the atmospheric pressure, somovements of the operation mechanism will be free. An air venteliminates a detrimental pressure possibility, which may constrict theclosing of the valve 12. In this way, button 9, rod 8, seal discs 10 and13, valve seat 11, valve 12, spring seat 14, return srping I5 and theretainer 16, constitute the whole of the operating mechanism. In theinjection process production; retainer 16 will be an integral part ofhousing 1. Connecting sleeve 17, is fixed under pressure in housing I,and permits by transition through hose 21 the connecting of the testingdevice to the engine intake manifold. The connecting sleeve or nipplel8, fixed under pressure in housing 1, permits, by way of hose 20, theconnection of the testing device to the vacuum chamber to be checked. Inthe injection process production, the connecting sleeves I7 and 18 willbe possible integral parts of housing 1. Rubber hoses and 21, have a 5 4inch diameter and a sufficient length of approximately 2 k feet, so thatthe operator can do the tests easily. Also, two adapters (not shown)permit the connecting of the testing device to any different hose sizesused.

Filter 19 eliminates all harmful particles, which can penetrate into thetesting device and affect its proper operation.

Here is briefly the operation of the testing.

When hose 20 is connected on the vacuum chamber to be checked and hose21 is connected to the intake manifold connector of a running engine; avacuum is created in the testing device main passage up to the operatingvalve 12, which is closed to let air into the other section of the mainpassage. But, when the operator presses down on the operating button 9,rod 8 transmits action to seal disc 10, and to operating valve 12, whichlifts slightly from seat 11, to open the main passage, and permits thevacuum to be created in the vacuum chamher (not illustrated); by way offilter 19 and hose 20. On vacuum action the diaphragm 4 plunges with theindicator 3, compressing the return spring 2. Operating button 9 is thenreleased and as this time the main passage is closed again by valve 12,by means of pressure action of return spring 15, which forces the rod 8and the operating button 9 to move back to the original position. Ifthere is no air leak, the indicator 3 will be in 'plunged inwardposition and remain. A leak in the vacuum chamber or its conduit willcause the air to penetrate into the main passage of the testing device,thus replacing the vacuum and so permitting the return spring 2 to pushup the diaphragm 4 and indicator 3, to reveal that a leak exists.

Instructions to use this testing device.

Caution.

This testing device operates in only one direction, and consequently,the following indications must be observed, to properly connect thistesting device on the car.

Connect hose 21 to the engine intake manifold connector, and hose 20 tothe vacuum chamber to be checked.

Have the engine running at idle.

Press on the operating button 9, until the indicator 3 is totallyplunged, and release button 9.

If the indicator 3 plunges down nearest to the surface of housing 1 andremains after the button 9 is released; this represents an indication ofa no leak condition.

If indicator 3 plunges down partially; or that is, goes up after thebutton 9 is released, this represents a leak indication.

When a leak is found, the same procedure must be repeated to check eachvacuum chamber separately, so as to localize the one which is faulty,and at the same time eliminate the possibility of faulty hoseconnections. It is now easy to find the faulty unit, and replace It.

Here is some useful recommendations, relative to the use of this testingdevice.

The tightness of this device can be easily checked by a lack of a vacuumat the end of hose 20, when the operating button is released, and hose21 is connected to a running engine. Also, the same result can beobtained by the obturation of hose 20 and by pressing down on operatingbutton 9 and releasing the same, and in temporarily disconnectingtemporarily hose 21 or momentarily stopping the engine. If at this time,the indicator 3 remains in the downward position; the tightness of thetesting device is ensured.

It should be advised to do some preliminary tests, before checking avacuum chamber, so that the possibility of a faulty testing device willbe eliminated and to keep a proper interpretation of the test. This isthe only precautionary measure, so that the leak possibilities in thetesting device are relatively low.

When we find a leak in the operating mechanism, and we think it is aforeign particle lodged between the operating valve 12 and its seat 11,it is recommended to do a cleanup of the testing device, by proceedingin the following manner: It suffices to completely press down operatingbutton 9 a few times, when the connecting sleeve 17 and hose 21 areconnected to a running engine intake manifold connector, and that hose20 and filter 19 are disconnected from connecting sleeve 18. Repeattightness test on the testing device another time. In the case where itis not possible to remove a harmful particule, this can be done, byusing compressed air with great precaution to eliminate the risk ofdamage to the testing device. Proceed in the following manner:Disconnect totally the testing device from the engine and remove hoses20 and 21 andfilter l9. Totally press down operating button 9 to fullyopen operating valve 12, and keep it open. Employ a little compressedair at reduced pressure to connecting sleeves l7 and 18. Repeat a fewtimes and also repeat the tightness test for the testing device.

I claim:

1. A leak testing device operated to detect a leak in a vacuum chamber,comprising a housing having a main passage extending therethrough, afirst connecting means secured to said housing in fluid communicationwith one end of said main passage and arranged to be connected to saidvacuum chamber, a second connecting means secured to said housing influid communication with the other end of said main passage, andarranged to be connected to a source of vacuum, a leak indicatingmechanism mounted onto said housing and including a peripherally sealedpressure responsive diaphragm, a first spring and an indicating memberoperatively associated to said diaphragm, the latter being arranged onone side of said main passage with one face thereof in fluidcommunication with said main passage, said indicating member beingconstructed and arranged to respond to the displacement of saiddiaphragm in response to the change of pressure against said one facethereof, an operating valve mechanism mounted onto said housingintermediate said lead indicating mechanism and said second connectingmeans, and including a tapering valve member having tapering facesarranged into the path of and intersecting said main passage, a secondspring associated to said tapering valve member and biasing the lattertowards a closing position sealing said main passage, and a manualoperating member operatively connected to said tapering valve member andarranged to displace the latter to an open position against the bias ofsaid second spring, whereby to selectively open said valve to evacuatesaid vacuum chamber and main passage and to close said valve and thendetect a leak into said chamber upon displacement of said indicatingmember.

2. A leak testing device as defined in claim 1, wherein said operatingvalve mechanism includes a tapering valve seat extending transversely ofsaid main passage and constructed and arranged to be tightly sealed bysaid tapering valve member upon transverse displacement thereof relativeto said main passage and a pair of flexible seal discs are arranged atopposite ends respectively of said tapering valve seat and of saidtapering valve member transversally confining and separating the latterfrom said second spring and said manual operating member respectively.

3. A leak testing device as defined in claim 2, wherein said firstspring engages said one face of said fluid responsive diaphragm andbiases the latter outwardly away from said main passage and saidindicating member constitutes an indicator rod engaging the oppositeface of said diaphragm and visually projecting outwardly of saidhousing.

4. A leak testing device as defined in claim 3, wherein said housingconstitutes a molded block having a rectilinear passage therethroughforming said main passage, and said first and second connecting meansconstitute hose connecting sleeve members secured to to said moldedblock.

1. A leak testing device operated to detect a leak in a vacuum chamber,comprising a housing having a main passage extending therethrough, afirst connecting means secured to said housing in fluid communicationwith one end of said main passage and arranged to be connected to saidvacuum chamber, a second connecting means secured to said housing influid communication with the other end of said main passage, andarranged to be connected to a source of vacuum, a leak indicatingmechanism mounted onto said housing and including a peripherally sealedpressure responsive diaphragm, a first spring and an indicating memberoperatively associated to said diaphragm, the latter being arranged onone side of said main passage with one faCe thereof in fluidcommunication with said main passage, said indicating member beingconstructed and arranged to respond to the displacement of saiddiaphragm in response to the change of pressure against said one facethereof, an operating valve mechanism mounted onto said housingintermediate said lead indicating mechanism and said second connectingmeans, and including a tapering valve member having tapering facesarranged into the path of and intersecting said main passage, a secondspring associated to said tapering valve member and biasing the lattertowards a closing position sealing said main passage, and a manualoperating member operatively connected to said tapering valve member andarranged to displace the latter to an open position against the bias ofsaid second spring, whereby to selectively open said valve to evacuatesaid vacuum chamber and main passage and to close said valve and thendetect a leak into said chamber upon displacement of said indicatingmember.
 2. A leak testing device as defined in claim 1, wherein saidoperating valve mechanism includes a tapering valve seat extendingtransversely of said main passage and constructed and arranged to betightly sealed by said tapering valve member upon transversedisplacement thereof relative to said main passage and a pair offlexible seal discs are arranged at opposite ends respectively of saidtapering valve seat and of said tapering valve member transversallyconfining and separating the latter from said second spring and saidmanual operating member respectively.
 3. A leak testing device asdefined in claim 2, wherein said first spring engages said one face ofsaid fluid responsive diaphragm and biases the latter outwardly awayfrom said main passage and said indicating member constitutes anindicator rod engaging the opposite face of said diaphragm and visuallyprojecting outwardly of said housing.
 4. A leak testing device asdefined in claim 3, wherein said housing constitutes a molded blockhaving a rectilinear passage therethrough forming said main passage, andsaid first and second connecting means constitute hose connecting sleevemembers secured to to said molded block.